Die Geschwindigkeitsabhängigkeit totaler Streuquerschnitte von Alkalien an Edelgasen

The velocity dependence of the total scattering cross section has been measured for 10 different combinations of alkali atoms with rare gas atoms. By means of an automated fast comparison technique the precision of relative values ofQ(ν) can be increased to 10^?3. In the eight cases where Ar, Kr or Xe is the scattering gas, undulations ofQ(ν) about its mean value have been observed. The precision of the method allows us in these cases to extract reliable information on the amplitude of the undulations. Use of this additional information makes it impossible to explain the experimental results with the simple, 2- or 3-parameter potentials that are generally used. Deferring a final evaluation to a later paper, we restrict ourselves here to giving, for the Lennard-Jones (8?6) potential, a table of?r _m values.